Qui peux m aider svp

Bonjour,

a)

( -7/50)( 3/3)  + (2/75)( 2/2)=

-21/150  + 4/150 =  -17/150

b)

1/5 * 3/3 -  2/3 * 5/5=

3/15 - 10/15 =  -7/15

c)

1/12 * 3/3  - 1/9 * 4/4=

3/36 - 4/36 =  -1/36

d)

 4/18 * 6/6  + 5/27 * 4/4=

24/108 + 20/ 108 =  44/108 = 22/54= 11/27